1. Field of the Invention
This invention relates to dental burrs, and in particular to a self-limiting occlusal reduction burr and method of use.
2. Background of the Invention
One of the more common dental procedures currently performed is the installation of a crown on a tooth whose state of decay is such that a filling is not a viable option. The tooth must first be prepared by removal of sufficient tooth material so that a ceramist can create a crown whose appearance is realistic. At the same time, excessive tooth material should not be removed during this preparation step, in order that the maximum feasible amount of good tooth be left intact. The problem of removing the correct amount of tooth material becomes more difficult where occlusal grooves are present. In this case, the deepest part of the occlusal groove should be reached by the reduction tool used, so that enough material is removed.
Existing Designs
One approach suggested to permit tooth reductions of a pre-determined depth to be made is illustrated in U.S. Pat. Nos. 2,280,927, 5,403,187, 4,526,542, 3,576,076, 5,100,322, and 5,890,897, granted to Phillips, Wauchope, Kochis, Weissman, Weissman, and Kruger et al. respectively. The apparatuses of these patents all incorporate a disc-shaped drill stop attached to a drill. When the drill has progressed to a certain depth, the drill stop impinges on the tooth being reduced, and prevents further reduction depth from being achieved.
There are a number of problems associated with this approach. During the tooth preparation step, cooling air/water spray must be constantly played on the cutting surface, in order to prevent over-heating of the tooth being reduced. If insufficient cooling is achieved, the tooth could overheat and suffer nerve damage. Because these prior art disc-shaped stops are possessed of flat faces facing the tooth, it is difficult to get the cooling air/water spray into contact with the drill cutting edges.
Another problem is that the flat faces adjacent the tooth prevent the cutting edge from adequately penetrating the tooth in order to remove sufficient tooth material from the bottom of occlusal grooves. If insufficient material is removed from the tooth being prepared, then it is difficult for the ceramist to make the crown appear realistic.
Accordingly, it is an object of the present invention to provide a self-limiting occlusal reduction burr which can quickly and easily reduce a tooth surface to a pre-determined depth. Design features allowing this object to be accomplished include a burr having a pre-determined burr length, and a shoulder. Advantages associated with the accomplishment of this object include reduced time to make tooth surface reductions, along with the associated cost savings and reduction in patient discomfit time.
It is another object of the present invention to provide a self-limiting occlusal reduction burr whose geometry allows coolant spray to be sent directly to a tooth groove being cut. Design features allowing this object to be accomplished include a conical shoulder having a major diameter and a minor diameter, a shank attached to the shoulder at the shoulder major diameter, and a burr attached to the shoulder at the shoulder minor diameter. Benefits associated with the accomplishment of this object include better tooth cooling during the reduction operation, consequently less chance of tooth nerve damage, and the associated reduction in patient discomfit.
It is still another object of this invention to provide a self-limiting occlusal reduction burr capable of removing sufficient material from fissures. Design features enabling the accomplishment of this object include a conical shoulder having a major diameter and a minor diameter, a shank attached to the shoulder at the shoulder major diameter, and a burr attached to the shoulder at the shoulder minor diameter. Advantages associated with the realization of this object include more accurate tooth material removal and crowns whose appearance is more realistic.
It is another object of the present invention to provide a method of use for a self-limiting occlusal reduction burr which provides for quick and accurate reduction of a tooth in preparation for attachment of a crown. Method steps allowing this object to be accomplished include determining an appropriate depth reduction required for a given tooth surface, selecting a self-limiting occlusal reduction burr having a burr length and/or burr diameter sized to yield the depth reduction previously determined, making a groove pattern using the self-limiting occlusal reduction burr selected, and using the self-limiting occlusal reduction burr to connect the grooves in order to yield a tooth reduction of the depth previously determined. Benefits associated with the accomplishment of this object include reduced time to make tooth surface reductions, along with the associated cost savings and reduction in patient discomfit time.